RFTools Activity Probe
Normally dimensions use power constantly. Even when nobody is in them. It is possible to make this a bit more efficient by making an Activity Probe. You can craft this block as follows:
This device is passive. It doesn't use any power and it has no user interface either. You simply place it in an RFTools dimension (it has no effect in any other dimension). While it is present in a dimension it monitors activity in that dimension and it will shut down power consumption from that dimension when nobody is in the dimension (including chunk loaders). So this block is an effective way to make sure your dimension isn't using power needlessly.